Beta Blockers and Palpitations

[Sue143]

Hello Again! I want to thank you so much for giving us the oppurtunity to ask questions here and somebody actually listens. I posted a question here recently how I started taking Toprol xl 25mg after having A-fib for the first time. I had a large increase in palps. from my normal of 1-10 a day(ocassionally more and sometimes none!), to 200-300 a day and one day I had 2000+. So they switched me to Atenol 25mg. I was ok with a small amount of palps. for 2 wks and then they started to get worse again. I had alot of them yesterday and they triggered tachycardia. I went to the ER and the Dr. there tells me that I would just like to think I would be better with no meds. but that I probably have just gotten worse over time. So I call my Dr. who is new to my case because of new insurance and he tells me "Beta- blockers will not do that." He told me to up my dose of Atenol to 50mg. I told him I was concerned because of all the palps and I think they will get worse. He says that can't happen. My resting heart rate at home is 60. How much lower can it go?
I've had palps for 6 1/2 yrs and they only got this bad after the a-fib incident and I started to take Toprol. I don't know whether to increase the dose and see what happens or stop the meds and see if they slow down again. I'm worried either way. He did say it doesn't look like I have WPW. They think my palps just coincidently got worse after the a-fib.
I see another Dr. next Thurs. as long as they don't cancel my appt. again.
Thanks so much! Sue

[Sue143]

Thanks to everyone! It just feels good to just know you're not alone. Mo I don't feel any palps during tachycardia, but on the other hand, it was a strong palp that actually stopped the tachy. I just can't see how my number of palps went down the tubes after having a-fib. Can a-fib make everything worse suddenly, does anyone know?
Thanks, Sue

[wingtip]

I was moved from CCB back to beta because my sleeping heart rate was down to 15bpm.  My resting heart rate is about 50.  The doctors don't seem to think that a low heart rate is a problem unless you pass out.  Because I have cronic a-fib, it's also not a problem when my HR goes over 200.  It seems like, if they do the tests and there are no other heart problems, the rate really doesn't matter, unless it cause you to over focus on the problems.

[Dr. Erik]

Beta Blockers don't actually cause palpitations. However, they slow the heart rythm down to the point that palpitations are more noticeable. When we are Beta Blocker-free are hearts beat faster and that in itself supresses the palpitations. The heart's pacemaker does't have time to fire off a premature beat when the heart is beating fast enough. You'll probably notice that during Tachycardia you never feel these premature beats. But Beta Blockers and Calcium Channel Blockers will prevent some people from having an episode of A-Fib. I take both Toprol XL and Cardizem and I haven't had A-Fib in two years. Good luck to you.

[Sue143]

I forgot to mention that alot of these palps actually feel different than when I don't take meds. If that means anything.
Thanks

[CCF-M.D.-RCJ]

Sue,

Thanks for the post.

First, some patients can develop worsening palpitations with beta-blockers, although this is uncommon.  The patients who develop this usually have vagally-mediated atrial fibrillation so that when the get a slower resting heart rate, it triggers afib.  One way to see if the beta-blockers are causing a real phenomenon is to up the dose as you were advised, but do so while wearing an event monitor.  This way, the doc can see what is happening when you are having symptoms.

Another possibility is that some people just feel their heart more when they are going slower.

A third possibility is that you have a baseline lowish blood pressure.  When you take the beta-blocker, your blood pressure drops further which leads to a compensatory increase in heart rate.  When you feel the relative tachycardia, then you develop anxiety which further speeds the heart rate, thus cauing a vicious cycle.  I see 2 or 3 patients per month that develop this type of syndrome.  The treatment is the combination of proper hydration and beta-blockers.

Don't worry too much about what is too slow.  You'll know that your rate is too slow when you begin to feel tired or run down.

Hope that helps.